Spray gun head



Oc 1965 J. L. KEMPTHORNE SPRAY GUN HEAD Filed Feb. 11. 1964 Fla. 8

INVENTOR.

JAMES L E WIS KEMPTHOR/VE United States Patent 3,214,103 SPRAY GUN HEAD James Lewis Kempthorne, 7 Ramsey Road, Montclair, NJ. Filed Feb. 11, 1964, Ser. No. 344,080 4 Claims. (Cl. 239-422) This invention relates to a spray gun head used for spraying fiocculated fibers and finely divided materials onto walls, ceilings, or other surfaces, for the purpose of fireproofing, noiseproofing, or providing heat insulation, or for other purposes.

The materials to be sprayed, as for example fibers of asbestos and rock wool, with an adhesive or cementing substance, are blown in a dry state, by compressed air, through a hose, and then centrally through a gun head. The latter usually has a circular series of nozzles surrounding the central opening, through which nozzles atomized water issues for the purpose of wetting the mentioned dry materials.

Due to the speed at which the dry materials are blown through the gun head, it has heretofore been found impossible to wet all of the material, with the result that the unwetted material does not adhere to the sprayed surface and falls to the floor. This falling out not only changes the appearance of the coating from that intended, but causes much dust which is annoying and unhealthful to operators, and results in waste material which has to be cleaned up and removed by extra labor. Moreover, some of the material which is partly but inadequately wetted temporarily stays on the sprayed surface and later drops off after the work is completed.

My present invention, by adequately wetting the dry material, eliminates the mentioned prior defects, producing a sprayed surface of intended appearance, eliminates waste, is more hygienic for operators, and requires no cleaning up of fallen material.

Another serious defect of gun heads is that the nozzles frequently become clogged, usually in about one-half hour of spraying, due to the very small atomizing orifice through which the air and water must pass. The usual gun head has two parts bolted together, with all the nozzles machined into the forward part. When one or more of the nozzles becomes clogged, the head has to be taken apart, which consumes time. Further, the nozzles are sometimes damaged in cleaning, and if only one of the nozzles is damaged the entire part containing them must be discarded, which is expensive. In the present gun head, the nozzles are individually formed and then screwed into the head, so that any one can be removed for cleaning or replacement without taking the head apart and without discarding undamaged nozzles.

The present gun head is also an advance in the art because it requires only a one horsepower air compressor as against a two-to-three horsepower compressor for gun heads having nozzles not using the combination of air and water in the nozzles.

The present gun head is also an improvement in that other and heavier aggregates may be sprayed due to the fact that the wetting action is complete. v

A still further advantage of the present head is that the distance of the head from the sprayed surface may be increased from the present three feet to about six feet, which increase in distance often enables ceilings to be sprayed from the floor without using scaffolding, which is expensive in time consumed in setting it up and taking it down, and its use results in a lower rate of coverage, which increased distance and resulting advantage is due to the fact that the cone of water and air carries more of the dry material to the ceiling, i.e., without loss.

A serious defect of prior gun heads has been that the sprayed water issuing from the circular series of nozzles has had gaps between adjacent nozzles, allowing some of the dry aggregate to escape being wetted. The present head, however, presents what may be termed a solid, taperedwall of atomized water, without gaps between the sprays from adjacent nozzles, which is partly due to the structure of the nozzles used and partly to using a sufiicient number of such nozzles. The nozzle structure is such that a fan-shaped spray issues from each nozzle so that, with the increased number of nozzles, the adjacent sprays intermix and thereby eliminate the usual gaps between sprays.

All spray guns in the past have had another serious defect. When spraying a ceiling, moisture runs down the gun head, wetting the operators hands and clothing. Not only is he then uncomfortable but it effects the quality and quantity of work being done. So serious is this defeet that the electric switch which is taped to the gun head, and which is used to start and stop the spray equipment, becomes grounded, and great care has to be taken to provide a waterproof switch to prevent the operator from getting a serious shock. I overcome this defect by providing a curved shield on the head to act as umbrella. The dripping moisture will then fall onto the shield and then to the floor.

The drawings illustrate the invention, and in these:

FIG. 1 is a side elevation of a gun head embodying the invention and shows a tapered or conical spray issuing therefrom onto a surface;

FIG. 2 is a longitudinal section on line 2-2 of FIG. 3;

FIG. 3 is a plan view of FIG. 1, omitting the shield which is fragmentarily shown in FIG. 1;

FIG. 4 is a side or elevational view of a nozzle used in the head;

FIG. 5 is a view of the top of the nozzle;

FIG. 6 is a longitudinal section of the nozzle on line 66 of FIG. 5;

FIG. 7 is a plan view of the front end of a head in which adjacent nozzles are inclined inwardly at different angles; and

FIG. 8 is a partial side view of the head with a watershedding shield attached.

Referring to the drawings for a detailed description, the gun head comprises a lower circular plate 10 and an upper overlying circular plate 12, which plates are detachably connected together in any suitable manner and are centrally apertured to receive a pipe 13 through which dry material previously mentioned is blown. Plate 12 has an inner circular channel 15 formed in its lower surface, and also an outer circular channel 16. The lower plate 10 has an oblique passageway 17 upwardly therethrough and communicates with circular channel 16 and also with the bore of a water supply pipe 18, said pipe being attached to a plate 19 which is secured to the bottom of plate 10, a shut-off valve 20 being provided in the pipe. The inner circular channel 15 of plate 12 communicates with an oblique passageway 22 formed in the plate 10 and also with the bore of a compressed air pipe 24. The latter is screwed into a plate 25 which is attached to the bottom of plate 10, the pipe having a shut-off valve 27. From the outer circular channel 16, oblique channels 28 rise into internally threaded recesses formed in the upper or front end of plate 12, and oblique channels 29 rise from the inner circular channel 15 into said recesses, which channels are convergent.

Sixteen nozzles 30 are separately screwed into said recesses and are preferably inclined inwardly, so that the resulting spray is conical, as illustrated in FIG. 1, said spray shown in FIG. 1 as being applied to a wall or ceiling 32. Sixteen nozzles are used instead of the usual eight, the purpose being to produce a spray which is continuous, i.e., without gaps between the sprays of adjacent nozzles, whereby a thorough wetting action on the dry material is produced. For certain applications, it is desirable to have half the nozzles at one angle, and half at another angle, with alternate nozzles being at the same angle, so that there will be two cones of different taper, of which one wets part of the material and the other part.

The nozzles 30 being similar, the construction of one will be described. The nozzle has a central bore 32 extending from its lower end to almost its upper end. The lower end portion of the bore is enlarged to form a mixing chamber 34 for the air and water which enter it from channels 28 and 29. A groove 33 is cut straight across and into the upper end of the nozzle, which groove is concave in depth, i.e., the bottom of the groove is concave, and its middle or lowest portion only reaches into the central part of the top of the bore 32 to make a very small oval atomizing opening 35 of smaller major diameter than the diameter of the bore, with a minor diameter the width of the groove. The resulting spray of air and atomized water is fan-shaped due to the oval hole and the adjoining groove 33 through which the spray emerges at both ends thereof.

As previously stated, the invention includes a Watershedding shield 40 which is attached to the periphery of the head and extends outwardly therefrom, and has a convex upper surface, as shown in FIG. 8, to direct the falling spray from the head and from the operator.

Modifications may be made within the concept of the invention. For example, the use of the nozzles giving a fan-shaped spray enables the operator to do a fair job without the use of compressed air therethrough, although not so good a job as when using air.

What is claimed is:

1. A spray gun head comprising a body having a circular central opening through which dry material may be blown, a circular series of nozzles individually attached to the front end of the body and inclined inward axially to collectively form a cone-shaped spray, each of said nozzles having a fan-shaped spray outlet to produce a fan-shaped spray, the nozzles being positioned immediately adjacent one another in the circular series such that adjacent fan-shaped sprays from the nozzles intermix and the circular series of sprays form a continuous cone-shaped spray, to avoid gaps between sprays from the individual nozzles.

2. The spray gun head specified in claim 1, in combination with a shield secured to the head and extending outwardly therefrom and inclined downwardly and outwardly to prevent water in the spray from dropping on the operator or on the usual electric switch taped to a spray gun.

3. A spray gun head having a central opening through which dry material may be blown, a circular series of nozzles individually attached to the front end of the body and extending forwardly thereof, the body having a circular air channel and a circular water channel, said nozzles each having a longitudinal bore and a mixing chamber at the inner end portion of the bore and having a fan-shaped spray outlet at the other end thereof, the body of the head having channels leading from said circular air and water channels into the mixing chamber of each nozzle, each of said channels being directed into said mixing chamber at an angle to the axis of said longitudinal bore.

4. The spray gun head specified in claim 3, in which the nozzles are positioned immediately adjacent one an other such that adjacent fan-shaped sprays from the nozzles intermix so that the series of sprays form a continuous cone-shaped spray, to avoid gaps between adjacent sprays from the individual nozzles.

References (Iited by the Examiner UNITED STATES PATENTS 1,630,974 5/27 Shelor et al. 239590 2,433,463 12/47 Lampe 239422 2,489,031 11/49 Hillringhouse 239428 2,522,928 9/50 Carroll 239590 2,578,412 12/51 Fisher 239424 2,585,133 2/52 Kempthorne 239422 2,597,573 5/52 De Groff 239--288 2,683,625 7/54 Fisher 239422 2,701,412 2/55 Wahlin 239590 2,732,25 8 1/56 Fisher 239-422 2,779,478 1/57 Wahlin 239--590 3,03 8,750 6/62 Nielsen 239422 3,057,273 10/62 Wilson 239423 M. HENSON WOOD, 1a., Primary Examiner.

EVERETT W. KIRBY, Examiner. 

1. A SPRAY GUN HEAD COMPRISING A BODY HAVING A CIRCIRCULAR CENTRAL OPENING THROUGH WHICH DRY MATERIAL MAY BE BLOWN, A CIRCULAR SERIES OF NOZZLES INDIVIDUALLY ATTACHED TO THE FRONT END OF THE BODY AND INCLINED INWARD AXIALLY TO COLLECTIVELY FORM A CONE-SHAPED SPRAY, EACH OF SAID NOZZLES HAVING A FAN-SHAPED SPRAY OUTLET TO PRODUCE A FAN-SHAPED SPRAY, THE NOZZLES BEING POSITIONED IMMEDIATELY ADJACENT ONE ANOTHER IN THE CIRCULAR SERIES SUCH THAT ADJACENT FAN-SHAPED SPRAYS FROM THE NOZZLES IONTERMIX AND THE CIRCULAR SERIES OF SPRAYS FORM A CONTINUOUS CONE-SHAPED SPRAY, TO AVOID GAPS BETWEEN SPRAYS FROM THE INDIVIDUAL NOZZLES. 